image (str): The image name to use for the containers.
command (list of str or str): Command to run.
args (list of str): Arguments to the command.
constraints (list of str): Placement constraints.
container_labels (dict): Labels to apply to the container.
endpoint_spec (EndpointSpec): Properties that can be configured to

access and load balance a service. Default: None.

env (list of str): Environment variables, in the form

KEY=val.

hostname (string): Hostname to set on the container.
isolation (string): Isolation technology used by the service’s